ESAB announces comprehensive tube welding system

A complete tube-welding system has been launched by ESAB, comprising of a new range of A21 PRH enclosed tube welding tool, high-quality mechanised Tig welding sources, and a parameter documentation printer. Aimed at users in the food, drink, pharmaceutical and semiconductor industries where high-integrity welds are required on stainless steel tubing, the cost-effective system guarantees full compatibility between the various components.

For applications where it is necessary to protect the welding arc from the negative effects of air, an enclosed tool with a shielding gas is essential. ESAB's answer is the A21 PRH family of enclosed tube welding tools. These combine the enclosing and shielding functions with alignment, clamping and controlled rotation so that the welding process is virtually fully automated, with no filler required. Capable of welding thin-walled stainless steel tubes in a variety of diameters, the A21 PRH tools include integral water cooling and are extremely compact, for use in areas where space is restricted. Furthermore, because there is encoder feedback on the motor, it is possible to use different welding parameters for different sectors of the weld.

Three sizes of A21 PRH tool are available so that the full range of tube outside diameters that can be welded extends from 3 to 76.2 mm. The PRH 3-12 is an ultra-thin weld head that welds all types of microfittings and tubes from 3 to 12.7 mm diameter. For larger sizes, the PRH 3-38 welds tubes from 3 to 38.1 mm and the PRH 6-76 welds tubes from 6 to 76.2 mm diameter.

In the tightest spaces, the PRH 3-12 is used with interchangeable cartridges that match the tube diameter. For less restricted spaces, the PRH 3-12 is available with a cartridge that accepts interchangeable collets to suit the tube. This concept of interchangeable collets is also used on the PRH 3-38 and PRH 6-76. In addition to the wide range of cartridges and collets available for standard tube sizes, blank collets can be supplied so that customers can machine them to suit specific tube diameters.

Depending on the application requirements, there is a choice of four different mechanised Tig power sources that can be used with the A21 PRH tube welding tools to give high-quality welds and an extremely reliable, highly productive process; these four are the Prowelder 160, 250, 320 and Protig 450, all of which are equipped with state-of-the-art microprocessor-based controllers. However, due to their portability and effectiveness, the Prowelder 160 and 250 machines are particularly suited.

Each power source benefits from a powerful yet intuitive programming system that features a large display. A different set of welding parameters can be created for defined sectors of the weld; a PC card then makes it easy to store the program, copy it to another machine, or transfer it to a PC for archiving.

In addition to operating with the A21 PRH tube welding tools, the power sources can also be used in conjunction with a wide variety of welding tools and semi-automatic mechanised welding equipment.

The third element of ESAB's tube welding system is the parameter documentation printer. This device simply connects to the power source and records the programmed and measured welding parameters. As well as recording current, voltage, speed, wire and power for each sector, the printer also identifies the power source, date, time, run number and total time for the weld. As such, the printer is an essential item of equipment for quality assurance purposes, unless the more sophisticated Weldoc WMS 4000 weld monitoring documentation software is installed on an industrial PC connected to the power source.